Hot can I access the serial port? 1

[aryajur]

Hello,
Can anyone help me as to how can I access the serial port thru a Java application ?

 

[greeneka]

check out:

http://java.sun.com/products/javacomm/

 

[aryajur]

I tried the api and I tried to execute the following code in one of the examples:

import java.io.*;
import java.util.*;
import javax.comm.*;

public class SimpleWrite {
static Enumeration portList;
static CommPortIdentifier portId;
static String messageString = "Hello, world!\n";
static SerialPort serialPort;
static OutputStream outputStream;

public static void main(String[] args) {
portList = CommPortIdentifier.getPortIdentifiers();

while (portList.hasMoreElements()) {
portId = (CommPortIdentifier) portList.nextElement();
if (portId.getPortType() == CommPortIdentifier.PORT_SERIAL) {
if (portId.getName().equals("COM1&quot) {
//if (portId.getName().equals("/dev/term/a&quot) {
try {
serialPort = (SerialPort)
portId.open("SimpleWriteApp", 2000);
} catch (PortInUseException e) {}
try {
outputStream = serialPort.getOutputStream();
} catch (IOException e) {}
try {
serialPort.setSerialPortParams(9600,
SerialPort.DATABITS_8,
SerialPort.STOPBITS_1,
SerialPort.PARITY_NONE);
} catch (UnsupportedCommOperationException e) {}
try {
outputStream.write(messageString.getBytes());
} catch (IOException e) {}
}
}
}
}
}


It compiles fine but when I execute it it gives the message:

Exception in thread "main" java.lang.NoClassDefFoundError: SimpleWrite

What is wrong here??

 

[sedj]

The directory that you have your SimpleWrite.class file is not in your CLASSPATH.

In the console you will run your code, do

(in dos)
set CLASSPATH=%CLASSPATH%;.

(in unix/linux [syntax for csh a bit different mind])
export CLASSPATH=$CLASSPATH:.